Moistdreproof article



Reissued Sept. 6, 1938 UNITED STATES PATENT OFFICE HOIS'I'UBEPROOFARTICLE No 1mm. Original m: aosasss, dated November 9, 1937, Serial No.758,651, December 21, 1934. Application rolreissue May 10, 193s,

Serial No. 207,152

11 Claims.

This invention relates to the art of moistureproofing. Moreparticularly, it relates to a composition of matter suitable for theproduction of moistureproof materials and also to the mois- I 6tureproof materials per se.

We believe that moistureproofing is due to (1) the use of an agent whichis inherently moistureprooi', and (2) the laying down of this agent in acontinuous unbroken film, either alone or 10 in combination with othermaterials or vehicles hereinafter called film-forming substances.

We have found, as a result of a large number of experiments, thatsubstances are inherently moistureproof when they are of such a naturethat they are not only insoluble in water but also dissolve none or atleast only an infinitesimal amount of water. Apparently, water vapordiffuses through continuous unbroken films of such substances by aprocess of dissolving in the film and evaporating from the other side.The solubility of water in the moistureproofing agent largely determinesthe rate of transfusion of water vapor through the film, and thereforeits inherent moistureproofness. Obviously, if

the film is non-continuous and broken, other factors enter into thedetermination of the degree of moistureproofness.

We have found that amides of the type hereafter more fully described canbe used in the preparation of moistureproofing compositions which willyield moistureproof films, i. e., coatings or self-sustaining filmswhich are preferably also transparent, glossy, non-tacky, flexible,possess good surface slip, etc.

For the purposes of this specification and claims, we definemoistureproof materials as those which, in the form of continuousunbroken sheets or films, permit the passage of not more than 570 gramsof water vapor per 100 square meters per hour, over a period of 24hours, at

approximately 35 C.:0.2 C., the relative humidity of the atmosphere atone side of the film being maintained at least at 98% and the relativehumidity of the atmosphere at the other side being maintained at such avalue as to give. a humidity differential of at least Moistureproofingcoating compositions are defined as those which, when laid down in theform of a thin, continuous, unbroken film applied uni- 50 formly as acoating with a total coating thickness not exceeding 0.0005" to bothsides of a. sheet of regenerated cellulose of thickness approximately0.0009", will produce a coated product which is moistureproof.

For the purpose of experimental tests, especially for those materialsadaptable as coating compositions, moistureproof materials include thosesubstances, compounds or compositions which, when laid down in the formof a continuous unbroken film applied uniformly as a coating with atotal coating thickness not exceeding 0.0005" to both sides of a sheetof regenerated cellulose of thickness approximately 0.0009", willproduce a coated sheet which will permit the passage therethrough of notmore than 570 grams of water vapor per square meters per hour over aperiod of approximately 24 hours,'at a temperature of 35 0.10.2 C., witha water vapor pressure differential of 40-44 mm'. (preferably 41.81031mm.) of mercury. For convenience, the number of grams of water vaporpassed under these conditions may be referred to as "the permeabilityvalue. An uncoated sheet of regenerated cellulose having a thickness ofapproximately 0.0009" will show a permeability value of the order of5700.

From the foregoing, it is apparent that under the conditions set forth,a moistureproofed regenerated cellulose sheet is capable of resistingthe passage of moisture or water vapor therethrough at least 10 times aseffectively as the uncoated regenerated cellulose sheet.

We have specifically defined herein moistureproofness in terms of apermeability test performed at substantially 35 C. It is to beunderstood, however, that by the adoption of this condition nodisclaimer is made of moistureproofness of any of the materials orcompositions when tested at temperatures lower than 35 C. Likewise, nodisclaimer is made of moistureproofing effects exhibited by thematerials herein described at temperatures above 35 C. There will be atemperature for each moistureproofing agent above which neither it norcompositions containing it show substantial resistance to the passage ofmoisture. However, this behavior does not disqualify the materialsherein described as moistureproofing agents.

The critical temperature above which these agents no longer exhibitmoistureproof properties is dependent primarily upon the melting pointof the material and upon the nature and composition of the film-formingsubstance with which it is used. Agents of higher melting points willshow moistureproof properties up to higher temperatures than will agentsof lowmelting points, other conditions being equal. Generally speaking,the agents of higher melting points .will be preferred for this reason,though for certainotherpm'posesitmaybedefinitelyadvisable to use agentsof lower melting points.

It is, therefore, an object of this invention to provide a composition01' matter suitable for casting or coating purposes comprising afilmiorming substance and an amide, more fully described hereafter,which will deposit a moistureproof film,'l. e. a self-sustaining film orcoating which .is preferably also transparent, flexible, non-tam, glossyand possesses good surface slip.

Another object of this invention is to provide moistureprooi' films, i.e. self-sustaining films or coatings containing amides which impartmolstureproofness'thereto, said films being prefembodiment, thecomposition also includes a solproofing eifect.

vent or solvent mixture, a plasticizer and/or a blending agent.

As the agents which aflord the basis for the moistureproofness, theinstant invention contemplates solid amides which are inherentlymoistureprooi' and have a melting point of at least 37' C. The moleculeof the moistureproof amide is largely hydrocarbon carbon, but maycontain the usual modifying groups, such as hydroxyl, carbonyl,.halogen, ester, etc., providing it has a suillciently high hydrocarboncarbon content to oifset the afiinity for water for these substituentgroups. In so far as this specification is concerned, a hydrocarboncarbon atom is one which has at least three of its valences attached tocarbon or hydrogen.

When an amide containing no modifying group in the molecule is used asthe moistureproofing agent, we have found that the molecule must containat least 17 hydrocarbon ,carbon atoms in the hydrocarbon portion thereoffor the amide group (CON) in order to achieve a moisture- When more than17 hydrocarbon carbon atoms are present, better moistureproofing efiectsare secured.

The amides contemplated by the instant invention may be aliphatic,aromatic or mixed aliphatic-aromatic or substituted amides. Any

when the number of active groups is increased,

for example, when two similar active groups are present, the limitingratio may be 55%-66% of the limiting ratio for one such group, while forthree similar active groups the limiting ratio is i5%55%) and approachesa limiting value of 30% as the number of similar active groups isfurther increased. When diiferent active groups are introduced, thelimiting ratio 01' hydrocarbon carbon atoms will vary, depending on thenature and number of such groups. Thus, for example, if two diiferentactive groups are present, the limiting ratio 01 hydrocarbon carbonatoms to active groups will be 55%'66% of the mean of the limitingratios for each of the individual active groups.

Btearamide, N-butyl .stearamide andstearanF lide are specificillustrative examples of amides which are moistureprooi and can beutilised in the preparation of molstureproot films.

As previously mentioned, the composition also contains a film-formingsubstance. As illustrative examples of film-forming substances may bementioned cellulose derivatives, for example, cellulose nitrate,cellulose acetate, ethyl cellulose, benzyl cellulose, mixed esters orether esters; resins, either natural or synthetic, such as rosin,

, hydrogenated ronn and its derivatives, including glycerol, glycol ordiethylene glycol esters of hydrogenated rosin; roan esters of glycerol,glycol or diethylene glycol; gum dammar; polybssic acld-polyhydrlealcohol resins, either modified or unmodified; vinyl resins of thepolymerized vinyl acetate, polymerized chlor-vinylacetate andpolymerized vinyl acetal resin types; metastyrene resin; phenoliccondensation products; rubber, gutta percha, balata, caoutchouc;synthetic rubbers including polymers of isoprene, butadiene and theirhomologues; chemical derivatives of rubber, such as halogenated rubber,rubber treated with sulphuric acid, rubber treated with tintetrachloride; rubber treated with chlorostannlc acid; varnishes: etc.One or a plurality of filmforming ingredients may be used. The precisefilm-forming ingredient or mixture thereof depends upon the purpose forwhich the compoutions are to be used.

When the composition contains a softener, any suitable softener for thefilm-forming ingredients may be used. For example, diamyl phthalate,tricresyl phosphate, dicyclohexyl phthalate, butyl benzoyl benzoate,etc., may be used, when the film-forming ingredient is a cellulosederivative.

In some compositions wherein a cellulose derivative is used, the filmwhich is produced may be hazy. If desired, this may be overcome byincorporating in such a composition a blending agent. Such compositionsalso are generally more moistureprooi than those without the blendingagent or gum. The blending agent tends to improve the compatibility oithe moistureproofing agents with the other ingredients in the film andconsequently the impermeability of the film. As several illustrativeexamples of blending agents may be mentioned gums or resins, such asdammar, gum elemi, ester gum, hydrogenated rosin; hydrogenated ester gumor the like, halogenated diphenyl, a natural occurring balsam or asynthetic balsam-like substanm, such as diethylene glycol hydrorosinate,or a substance such as lanum, hydrogenated castor oil. di-dodecylphthalate, retene, diricinoleic ester of glycerol or the like.

The ingredients which constitute the final film may be dissolved in anappropriate. solvent or solvent mixture to form a solution which may beused as herein described. Alternatively, the ingredients constitutingthe final film may be used in the form of a melt. When the compositionis to be used in the form of a melt, it is desirable to include thereina blending agent to inhibit crystallization. Hydrogenated rubber,hydrogenated ester gum, rosin, dammar, diethylene glycol hydrorosinateand the like, are several illustrative examples of crystallizationinhibitors. Whenever the composition is in the form of a lacquer andused for coating purposes, the solvents thereof are chosen so that theywill not produce any deleterious effects on the base being coated.

The proper formulation of the lacquer so that it will yield coatingswhich are transparent and highly moisture-proof is determined by tests.One of the most important things to be determined is the proper amountof blending agent to be used. This can be determined, for example, asfollows: A series of compositions is prepared containing the sameamounts of lacquer base, softener, moistureproofing agent and solvent.Different quantities of blending agent are then added to each of theselacquers and the general properties, such as transparency and thepermeability values of sheets of regenerated cellulose, for example,coated with each of these compositions, are plotted against the ratio ofblending agent to moistureproofing agent used.

When a lacquer of the type described in Example IV is modified accordingto this systematic procedure, it will be found that the lowestpermeability value occurs very near the point where the coatings becomecompletely transparent. In the case of N-butyl stearamide in thisparticular composition, this point is equivalent to approximately 2.00to grams of dammar to 1 gram of N-butyl stearamide. It is obvious thatthis optimum blending agent-moistureproofing agent ratio will vary fordifferent moistureproofing agents and for different blending agents withthe same moistureproofing agent. In general, this ratio depends upon thehydrocarbon carbon content and the solubility of the moistureproofingagent in the lacquer solids. Thus, the ratio is high formoistureproofing agents having high hydrocar bon carbon content and lowfor moistureproofing agents which are quite soluble or compatible withthe other constituents of the coating. Undoubtedly, other factors, suchas melting point, solvent composition of the lacquer, type of lacquerbase used, choice of plasticizer, etc., also affect this optimum ratio,but the two considerations mentioned above seem to be the more importantones.

A series of experiments, based on the composition of Example IV will, ofcourse, have a pyroxylin lacquer base and a pyroxylin-moistureproofingagent ratio of 5.26:1. Obviously, this ratio can also be varied and therelations between permeability value and the blendingagentmoistureprooflng agent ratio determined for sheets of regeneratedcellulose coated with a series of lacquers having a different lacquerbasemoistureproofing agent ratio to which various amounts of dammar orother blending agent have been added. These relations will have the samegeneral character but it will be found generally that, as the lacquerbase-moistureproofing agent ratio is increased (decreasing the quantityof moistureproofing agent), the permeability values will be higher for agiven blending agent-moistureproofing agent ratio and will eventuallypass out of the..moistureproof limit. On the other hand, decreasing thisratio (increasing the moistureproofing agent) does not decrease thepermeability values indefinitely and, after a certain point is reached,may even decrease the moistureproofness. Experiments have shown that theoptimum lacquer base-moistureproofing agent ratio usually falls withinthe limits 1:10 to 200:1 and the blending agent-moistureproofing agentratio lies between the limits of 0:1 to :1. The most satisfactorycellulose derivative base-moistureproofing lacquers generally fallwithin these limits for.nearly all moistureproofing agents, the optimumpyroxylin-moistureproofing agent ratios being of the order of 2:1 to30:1. However, for certain purposes, for example, compositions forcasting moistureproof foil, the ratios may differ greatly from thosegiven above and we do not intend that we should be confined to theselimits which are suggested merely as an aid to the proper formulation ofmoistureproofing lacquers.

The above or any other method for determining the most satisfactoryformula in which to use any moistureproofing agent to achieve minimumpermeability and maximum clarity of coating may be used. The abovediscussion is merely given as one systematic method, whereby thecompositions may be formulated with the moistureproofing agents heredisclosed. Different moistureproofing agents will yield different dataon such a series of experiments as this, and moistureproofing agents ofdifferent chemical constitution will be formulated differently intovarious dopes or vehicles. There is thus no single composition such ashas been described above which is capable of universal application. Thespecific examples hereafter given are thus illustrative, and theabove-described method of systematically varying the compositions ofsolids in which a moistureproofing agent is used is exemplary of ageneral method, whereby optimum results may be achieved with an agent.The inethod is, of course, capable of extension to include variations ofany of the solid lacquer ingredients, or even to include solvents andthe solvent composition. Thus, when one skilled in the art is taught bythese disclosures, he will be able to formulate a variety ofcompositions containing any of the moistureproofing agents or todetermine those compositions with which our moistureproofing agents aremost advantageously used. A moistureproofing agent is thus not amaterial which will always and universally produce moistureproofcoatings utterly regardless of the composition in which it is used. Itusually requires to be formulated in certain favorable compositions tobring out its inherent moistureproofing properties. On the other hand, asubstance which is not inherently moistureproof cannot by any extendedamount of work in formulation be made to yield moistureproof films orcoatings. Thus, when we speak of the inherent property of a compound tomoistureproof, we are concerned with a specific inherent property whichpermits it to be used with some film-forming vehicle to producemoistureproof coatings.

The composition can be used for the production of films, either bycasting it in the well-known manner to produce self-sustaining films, orby coating it on to the selected base. When the composition is to beused as a coating, any suitable base material, paper, highly calenderedpaper, glassine, leather, fabrics, etc., may be used. The compositionsmay even be applied to metals to prevent them from rust by virtue oftheir moistureproofing property. They may also be used to coatindividual fibers of cotton, wool or artificial silk in such a manner asto make them molstureproof. In the preferred embodiment of theinvention. when a transparent wrapping tissue is desired, the base mayconsist of thin, dense, non-fibrous, substantially non-porous andpreferably transparent sheeting formed of a celluiosic, albumlnous orother material. As illustrative examples of cellulosic sheeting may bementioned cellulosic sheeting coagulated or precipitated from an aqueousdispersion or solution of a cellulosic material, for example, sheetingof regenerated cellulose, glycol cellulose, cellulose glycollic acid,lowly etherified or esterified cellulose, such as lowly methylatedcellulose; and

sheeting of cellulose derivatives, such as cellu-.

loss acetate, cellulose/ nitrate. ethyl cellulose.

benxyl cellulose. Gelatin and casein, hardened or not as desired, arementioned as illustrative examples of albuminous materials. Sheeting ofg rubberorrubberderlvati'vesinl-yalsobeusedas the base.

When a selected base, as for example relenerated cellulose sheeting, isto be moistureproofed, by the compositions hereinbefore described. thecoinposition is applied to the regenerated'cellulose sheeting in anysuitable manner, such as immersion. spraying, brushing, etc. The lacquermay be. if' necessary. maintained at the time of application at anelevated temperature in order to prevent separation of themoistureproofing ingredients. The excess composition is removed by anysuitable means and substantially all the volatile solvents are removedfrom the composition at an elevated temperature, 'for example, 90 C.-ll'0., in order to prevent separation or crystallimtion of themoistureproofing agent during evaporation of the solvent. It is alsopreferable to use air low in moisture content during the dryingoperation in order to obtain evaporation of the solvent without filmblush. After being dried, the product, if the base is of the type whichm moisture at elevated temperatures. may be subjected to a humidiiyingtreatment or other meeans for a sufiicient time to import or restoreflexibility and to deodorize. In some cases, the lacquer-coatedmaterials'may be air-dried at room temperature, in which case thehumldifying treatment is not needed;

Hereafter. there are set forth several illustrative specific examples inorder to more clearly explain the invention.

Zmample 1' (A) A composition consisting of the following 0 ingredientsin ately the proportions set forth is prepared in any convenient andappropriate manner:

Partsbyweight Pyroxylin 5.26

Gum dammar 8.25 Dibutyl phthalate 2.82 N-hutyl stearamide 1.00 Ethylacetate 46.25 Toluene 88.00

n Alcohol 6.28 Acetone 0.68

I coated sheet irom the uncoated sheet in appearance. However, thecoated sheet is moistureproof. having a permeability value of less than570. for example of the order of 200 or less. The coated sheet ismuchmore resistant to 10 thepassageofwatervaporthanasimilarsheet coated withthe same lacquer, except for the omission of N-butyl stearamide or asheet coated with a hish erode waterproof spar varnish. -A

sheet coated with the lacquer without the additime! N-butyl staramidewill have a permeeases ability value of 4.000 to 5,000, while the sheetcoated with a waterproof spar varnish willhave a permeability value offrom 2,000 to 4,000.

(a) minty] stearamide in Example 1(a) is substituted by an equal amountof stearamide.

' The process of Example HA) is utilised to coat the transparentregenerated cellulose sheeting.

Example 11 A composition consisting of the following ingredients inapproximately the proportions set forth is prepared by any well-knownprocedure:

. Parts by weight Ethyl cellulose 8.0 Realm--- 8.0 Tricresyl phosphate1.0 Btearanillde 1.0 Toluene 60.0 Alcohol 18.0 Ethyl lactate 10.0

Transparent sheets of regenerated cellulose are coated and treated inthe manner described in Example HA). The product is transparent,

flexible, glossy, has a good surface slip and a' permeability value ofthe order of 285 or less.

Further, compositions of this type may be used for protecting steel andother corrodible metals against rust or the like. The coatings may beair-dried at room temperature for 5 minutes and are times as impermeableto the diffusion of moisture vapors as similar coatings containing nomoistureproofing agent.

The omission of ethyl lactate from the above composition will provide acompomtion suitable for coating sheets of cellulose acetate and suchcoated sheets will have a permeability value of not more than 570 and ofthe order of 285 or less. This product is also transparent, flexible.glossy, non-tacky and possesses good surface slip.

As previously explained, in many cases it may be desirable to omit thegum or resin entirely, though when used it may materially improve thetransparency of the final product.

Example III A composition consisting of the following ingredients inapproximately the proportions set forth is prepared in any well knownmanner:

Parts by weight Ethyl cellulose 7.0 Dibutyl phthalate 2.0 N-butylstearamide 1.0 Toluene 62.0 Alcohol--- 21,0

Cellulose acetate sheeting is coated with this lacquer in accordancewith the procedure out-' lined in Example I(A) The product, after beingdried at room temperature, is flexible, glosy, has good surface slip anda permeability value of the order of 285 or less.

Example IV A composition consisting of the following ingradients inapproximately the proportions set.

forth is prepared in any well known manner:

Parts by weight Pyroxylin 5.26 Dibutyl phthalate 2.32 N-butyl stearamide1.00 Ethyl acetate 46.25 Toluene 36.00

Alcohol 6.28 Acetone 0.68

A highly calendered smooth paper is provided with a continuous layer ofthis lacquer by coating with or without impregnation, and then drying at90 C.-l C. The product has a permeability value of the order of 380 orless.

The compositions described in Examples III and IV yield coatings whichmay be slightly hazy. If transparency is essential, a blending agent ofthe type above mentioned may be incorporated in these compositions.Thus, lacquer described in Example IV may be so modifled that it alwayswill yield a transparent coating by the addition of a blending agent,such as dammar; the quantity of dammar or other blending agent addedmust be determined as previously described.

The following is an example of a composition wherein a polybasicacid-polyhydric alcohol resin constitutes the film-forming ingredient.This composition consisting of the following ingradients inapproximately the proportions given is prepared in any suitable manner:

Parts by weight Perilla oil polybasic acid-polyhydric alcohol resinvarnish Stearanilide l Toluen 50 The perilla oil polybasicacid-polyhydric alcohol resin varnish is prepared from the followingingredients:

Metallic cobalt (added as linoleate) Ethyl ace The procedure forpreparing the perilla oil polybasic acid-polyhydric alcohol resinvarnish is as follows: Heat 72.6 parts of C. P. Glycerin to 350 F. inclosed kettle-condenser and stirrer. At 350 F. add NaOH, followed byperilla oil. Stir rapidly and heat to 437 F. Hold until clear (15-30minutes). Add phthalic anhydride and heat to 392 F. Add residue ofglycerin to batch. Heat to 392 F. and hold (5 hours). Acid number 45-55.Cool to 175 F. Cut with ethyl acetate. Add drier and centrifuge. (Solids50%.)

Regenerated cellulose sheeting coated with this composition as explainedunder Example I(A) and dried at room temperature or at 90 C.- 110" C.produces a product having a permeability value of the order of 570 orless. A composition of this type may be used without blending agents,but in some cases it is advantageous to use a small amount of a blendingagent. Usually, compositions of this nature are suiiiciently flexiblewithout the addition of a plasticizer. Lacquers of this type may be usedwhen particularly good adhesion is desired.

for example, the' coatings, this becomes especially important.

As previously mentioned, another method of obtalning articles which areof themselves moistureproof is the casting of films containing theorganic amides as moistureproofing agents. The compositions given inExamples I-IV inclusive may be used for this purpose. It is usuallydesirable, however, to employ a higher solids base solution for castingsheets than is ordinarily used for forming thin coatings. Furthermore,in view of the greater thickness of cast foils as compared to coatings,a smaller proportion of the moistureproofing agent is used in order toobtain transparency and a high degree of moistureproofness, and this inturn will require the use of a smaller quantity of blending agent and/orthe use of blending agents other than hard gums in appreciablequantities. Those skilled in the art will be able to formulate by testssatisfactory compositions for the preparation of cast sheets.

The cast sheets and protective coatings prepared in accordance with theinstant invention have the ability to resist the transmission ordiffusion of water vapor to an extent at least 4 times that displayed bysheets of equal thickness and produced from similar or prior artcompositions formulatedwithout the addition of moistureproofing agents.The value 4 merely sets forth the minimum improvement and does not limitthe higher moistureproofness that can be obtained. The moistureproofingagents herein described are capable of being formulated into filmsshowing improvement over prior art films produced from compositionsformulated without the addition of moistureprooflng agents not only 4but 10, 20, 40 and in some cases even 100 fold. This is truly aremarkable accomplishment.

The compounds described in this application as moistureproofing agentshave many advantages. Molstureproofing compositions containing themolstureproofing agents are easily duplicated. As previously stated,these compositions in certain formulations thereof yield coatings whichair-dry at ordinary temperatures. For certain purposes where it is notfeasible to force-dry the As for the moistureprooflng agents themselves,they are generally colorless, odorless, tasteless, nonvolatile, andessentially non-toxic, at least in the quantities in which they areused, and they can bereproduced synthetically with a high degree ofuniformity and consistency.

In the definition hereinbefore set forth, it is to be understood thatthe permeability value of 570 represents only the maximum value. In manycases permeabilities of 235, 140, 57, 30 or indeed less may be obtained.

When bases of the preferred type are utilized, the ultimate product isadmirably suited for use as a transparent moistureproof wrapping tissue.

Since it is obvious that various changes and modifications may be madein the above description without departing from the nature or spiritthereof; this invention is not restricted thereto except as set forth inthe appended claims.

We claim:

1. An article of manufacture comprising a continuous moistureproofunbroken solid film comprising a film-forming substance and aninherently moistureproof N-aryl substituted amide having a melting pointof at least 37 C. as the moistureproofing agent, said amide containingno modifying groups in the molecule, having at least 17 hydrocarboncarbon atoms for the CON group and being present in an amount to impartmoistureproofness to the article.

2. An article of manufacture comprising a continuous moistureproofunbroken solid film comprising a film-forming substance, an inherentlymoistureproof N-aryl substituted amide having a melting point of atleast 37' C. as the moistureproofing agent, and a blending agent, theratio of the quantity of film-forming substance to the quantity of amidebeing within the limits of 1:10 to 200:1. and the ratio of the quantityof blendn! agent to the quantity of amide being within the limits of 0:1to 10:1, said amide containing no modifying groups in the molecule,having at least 17 hydrocarbon carbon atoms for the CON group and beingpresent in an amount to impart moistureproofness to the article.

8. An article of manufacture comprising a continuous moistureproofunbroken solid film comprising pyroxylin, an inherently moistureproofN-aryl substituted amide having a melting point of at least 37' C. asthe moistureproofing agent, and a blending agent, the ratio of thequantity of pyrozylin to the quantity of amide being within the limitsof 2:1 to :1, said amide containing no modifying groups in the molecule,having at least 17 hydrocarbon carbon atoms for the CON group and beingpresent in an amount to impart moistureproofness to the article.

4. An article of manufacture comprising a base having a moistureproofcoating comprising a film-forming substance and an inherentlymoistureproof N-aryl substituted amide. having a. melting point of atleast 37 C. as the moistureproofing agent, said amide containing nomodifying groups in the molecule, having at least 17 hydrocarbon carbonatoms for the CON group and being present in an amount to impartmoistureproofness to the article.

5. An article of manufacture comprising a transparent non-fibrous basesheet or film having a transparent moistureproof coating comprising afilm-forming substance and an inherently moistureproof N-arylsubstituted amide having a melting point of at least 37 C. as themoistureproofing agent, said amide containing no modifying groups in themolecule, having at least 17 hydrocarbon carbon atoms for the CON groupand being present in an amount to impart moistureproofness to thearticle.

6. An article of manufacture comprising a transparent regeneratedcellulose base sheet or film having a transparent moistureproof coatingcomprising a film-forming substance and an inherently moistureproofN-aryl substituted amide having a melting point of at least 37 C. as themoistureproofing agent, said amide containing no modifying groups in themolecule, having at least 17 hydrocarbon carbon atoms for the CON groupand being present in an amount to impart moistureproofness to thearticle.

7. An article of manufacture comprising acoutinuous moistureproofunbroken film comprising a film-forming substance and stearanilide asthe moistureproofing agent, said stearanilide being present in an amountto impart moistureproofness to said article.

8. An article of manufacture comprising a transparent non-fibrous basesheet or film having a continuous transparent moistureproof coatingcomprising a film-forming substance and stearanilide as themoistureproofing agent, said stearanilide being present in an amount toimpart moistureprooi'ness to said article.

9. An article of manufacture comprising a continuous moistureproofunbroken solid film comprising a film-forming substance. a solidinherently moistureproof N-aryl substituted amide having smeltingpointofatleast 37 C.asthe moistureproofing agent, and a blending agent,said amide containing no modifying groups in the molecule and beingselected from the group of inherently moistureproof N-aryl substitutedamides which consists'of (1) inherently moistureproof amides containingone CON group and at least 17 hydrocarbon carbon atoms for the CONgroup; (2) inherently moistureproof amides containing two CON groups andat least approximately 9 hydrocarbon carbon atoms for each CON group;(3) inherently moistureproof amides containing three CON groups and atleast approximately 8 hydrocarbon carbon atoms for each CON roup; and(4) inherently moistureproof amides containing more than three CONgroups and at least 5 hydrocarbon carbon atoms for each CON group, saidamide being present in an amount to impart moistureproofness to saidarticle.

10. An article of manufacture comprising a base having a continuousunbroken moistureproof coating comprising a film-forming substance, asolid inherently moistureproof N-aryl substituted amide having a meltingpoint of at least 37 C. as the moistureproofing agent, and a blendingagent, said amide containing no modifying groups in the molecule andbeing selected from the group of inherently moistureproof N-arylsubstituted amides which consists of (1) inherently moistureproof amidescontaining one CON group and at least 17 hydrocarbon carbon atoms forthe CON group; (2) inherently moistureproof amides containing two CONgroups and at least approximately 9 hydrocarbon carbon atoms for eachCON group; (3) inherently moistureproof amides containing three CONgroups and at least approaimately 8 hydrocarbon carbon atoms for eachCON group; and (4) inherently moistureproof amides containing more thanthree CON groups and at least 5 hydrocarbon carbon atoms for each CONgroup, said amide being present in an amount to impart moistureproofnessto said-article.

11. An article of manufacture comprising a transparent non-fibrous basesheet or film having a continuous t moistureproof coating comprising afilm-forming substance, a solid inherently moistureproof N-arylsubstituted amide havingameltingpointofat least37 C.asthemoisturepr'oofing agent, and a blending agent. said amide containing nomodifying groups in the molecule and being selected from the group ofinherently moistureproof N-aryl substituted amides which consists of (1)inherently moistureproof amides containing one CON group and at least 17hydrocarbon carbon atoms for the CON group; (2) inherently moistureproofamides containing two CON groups and at least approximately 9hydrocarbon carbon atoms for each CON group; (3) inherentlymoistureproof amides containing three CON groups and at leastapproximately 8 hydrocarbon carbon atoms for each CON group; and (4)inherently moistureproof amides containing more than three CON groupsand at least 5 hydrocarbon carbon atoms forv each CON group. said amidebeing present in an amount to impart moistureproofness to said article.

'WILLIAM HALE CHARGE. MERLIN MAR'I'IN BRUBAm.

